Development of the Dual-cathode Glow Discharge Lamp and the Analytical Application to Steel Materials

Abstract

A modulated hollow cathode lamp with three electrodes can provide a spectrum pattern of sputtered atoms (sample) separated from the overall emission signals. The optimum conditions for operating the lamp are investigated. An argon pressure and a frequency of the pulsed discharges are examined to obtain the intense and reliable emission intensities. A negative voltage loaded between the intermediate electrode and the cathode sample is an important parameter in order to eliminate the undesired argon emission lines. Emission intensities of the sample strongly depend on a variation in this voltage, while those from argon atoms and ions hardly change. Selective detection of the sample emission lines can be achieved by modulating the voltage at frequencies of 100-300Hz.